This invention concerns rotary engines of the type shown in U.S. Pat. No. 2,988,065 granted on June 13, 1961 to Wankel et al. More particularly, the invention concerns such engines having a throttle valve in the air intake passage adjacent to the downstream end of said passage such as shown in U.S. Pat. No. 3,347,213 granted Oct. 17, 1967 to Froede; U.S. Pat. No. 3,937,186 granted Feb. 10, 1976 to Stock; U.S. Pat. No. 3,916,846 granted Nov. 4, 1975 to Kromer; and U.S. Pat. No. 3,844,256 granted Oct. 29, 1974 to Ishikawa et al. In these prior patents the prime reason for so locating the throttle valve is to reduce the amount of exhaust gases which are drawn into the intake passage, particularly during idling operation of the engine as a result of overlap of the intake and exhaust passages, and to increase the flow-velocity of the intake charge into the engine working chambers.